Mixing target for combustion chambers having means to retard radial outward movement



H. GODDARD Filed May 11, 1946 M21 1. odaa 65M 6. 6oddazd,&}@c@

R. MIXING TARGET FOR COMBUSTION CHAMBERS HAVING MEANS TO RETARD RADIALOUTWARD MOVEMENT Aug. 12, 1952 Patented Aug. 12, 1952 MIXING TARGET FORCOMBUSTION CHAM- BER'S HAVING MEANS TO RETAR-D RADIAL OUTWARD MOVEMENTRobert H. Goddard, deceased, late of Annapolis, Md., by Esther C.Goddard, executrix, Paxton, Mass, assignor of one-half to The Daniel andFlorence Guggenheim Foundation, New York, N. Y., a corporation of NewYork Application May 11, 1946, Serial No. 669,056

Claims. 1

This invention relates to a combustion chamber particularly adapted foruse in rocket propulsion apparatus and of the type in which thecombustion elements are projected under pressure toward a closed orinner end portion of the combustion chamber.

The provision of a target area at the closed end of a combustion chambercauses the drops or sprays of combustion liquids striking the target tobe flattened out and to be superposed in the target area, thus becomingmuch more thoroughly mixed than where two open sprays merely intersectand only partially intermingle.

It is the general object of this invention to provide an improved targetconstruction by which more effective mixing of the combustion elementsis caused to take place.

To the attainment of this object, a target con struction is providedwhich retards the radial outward spreading of the drops or sprays awayfrom the target area and which thereby attains even more thorough mixingand intermingling of the combustion liquids.

The invention further relates to arrangements and combinations of partswhich will be hereinafter described and more particularly pointed out inthe appended claims.

Preferred forms of the invention are shown in the drawings, in whichFig. 1 is a partial sectional side elevation of a combustion chamberhaving one form of im proved target construction embodied therein;

Figs. 2 and 3 are sectional side elevations of modified and jacketedtarget members;

Fig. 4 is a partial sectional side elevation of a porous target member;

Fig. 5 is a similar View of a target member having fine perforations forcoolants;

Fig. 6 is a partial sectional elevation of a member having an annulartarget area;

Fig. '7 is an end elevation of a modified target member; 7 Fig. 8 is atransverse sectional view, taken along the line 8-8 in Fig. 7;

Fig. 9 is a sectional View similar to Fig. 8 but showing a furthermodification;

Fig. 10 is an end view of another form of target member;

Fig. 11 is a transverse sectional view, taken along the line I I-I I inFig. 10;

Figs. 12 and 13 are transverse sectional views of additionalmodifications;

Fig. 14 is an enlarged detail view of a portion of the structure shownin Fig. 13; and

Fig. 15 is a partial longitudinal section of a impact with the targetsurface I1.

- 2 jacketed combustion chamber and target member.

Referring to Fig. 1, portions of a combustion chamber C are shown havingan inner end extension It] provided with nozzles H and I2 through whichstreams of combustion liquids may be projected against a target memberId. The nozzles I I and I2 are preferably provided with inner helicalguiding members or rotators I 5 by which the liquids will be given arotating or whirling motion as they are injected under pressure againstthe target I4.

The operative face of the target I4 is provided with a target recess I6preferably having a concave impact surface I! and also having an annularoverhanging edge portion I8 which retards outward spreading of thecombustion liquids on Thorough and effective mixing of the combustionliquids accordingly takes place in the target recess I6. Theintermingled and ignited combustion elements pass into the combustionchamber C as indicated by the arrows in Fig. 1, the combustion processbeing completed in the chamber C.

In Fig. 2 a target member 20 is shown mounted on a tubular support 2|and provided with a jacket 22 supplied with a cooling liquid through apipe 23. The liquid thus supplied, after engaging and cooling the target20, passes out through slots or openings 24 to any suitable waste ordischarge. With this construction, thetarget member is effectivelycooled and may be made of relatively thin sheet metal.

In Fig. 3 a somewhat similar construction is provided for cooling atarget member 30 which is of very substantial depth. This type of targetmember allows the larger drops to engage the emerging stream of mixedliquids for a considerable distance before they strike the inner end ofthe target member. The emerging stream of mixed combustible elements isnarrower and more sharply defined than when produced by a target of thetype shown in Fig. 2. A cooling liquid is supplied through a pipe 3| tothe jacket casing 32 and flows out through openings 33 to a waste ordischarge, all as previously described.

In the construction shown in Fig. 4, the target member 35 has asubstantially semi-spherical target surface and is formed of porousmaterial, such as a porous metal or oxide, so that coolant suppliedthrough the tubular support 36 will effectively cool the target member35 and will be discharged to the combustion chamber through the pores ofthe target member.

In Fig. 5 a similar target member 40 is provided 3 with fineperforations 4| obliquely disposed with respect to the axis of thecombustion chamber, so that the cooling liquid will enter the chambersomewhat tangentially and so that the combustion liquids engaging thetarget will be prevented from passing in a direct line therethrough.

In Fig. 6 effective intermingling is produced by introducing twodifferent combustion liquids, as a liquid fuel and a liquid oxidizer,through nozzles 42 and 43 to the peripheral portion of the target member44 which has a generally concave target surface 45 but which is alsoprovided with an outwardly projecting axial portion 46, so that theintermingled combustion liquids-are projected along the axis asindicated by the arrows b and do .not intersect the sprays projectedfrom the .nozzles 42 and 43. I

In Figs. '7 and 8 a target member is shown in which special provision ismade for retarding outward spread of the liquids engaging the targetsurface. The target member 48 is provided with annular ridges 49disposed as shown in Fig. 8 and gradually decreasing in height towardthe axis. This variation in heightpermits the drops or sprays to spreadout more rapidly in .the central portion and to be increasingly retardedas they approach the periphery.

In Fig. 9 a target'member 50 is shown in which the annular ridges -I arerounded in section to better resist high temperature, by reason of theirincreased cross section and by their avoidance of sharp edges. Anoverhanging lip portion 52 is also provided, similar to theoverhangingportion 3 shown in Fig. land previously described.

In Figs. and 11 a .quite similar target member 55 is shown, except thatthe annular ridges previously described are replaced by annularseries-of spaced elongated projections 56, alter- .nately disposed inadjacent series.

Fig. 12 is a modification of the construction shown in Figs. 7 and 8 andshows a target member 60 having annular ridges SI of inwardly curvedcross section, so that outward spreading of the combustion liquids isadditionally retarded. The target member 60 also has an overhangingouter edge portion 62 similar to the edge portion 52 in Fig. 9 and theedge portion l8 in Fig. 1 and the outer edge portions are curved inwardor towards the axis.

Fig. 13 shows a further modification of .the construction shown in Figs.'7 and 8, with the target member 65 provided with annular ridges 66 ofcurved and hooked section, and with the hooked edges directed outwardlyand away from the axis, as more clearly shown in Fig. 14. Thisconstruction is designed to facilitate the thorough mixing andintermingling of the combustion liquids by the formation-of vorticesbetween the ridges, as indicated by the arrows in Fig. 1.4.

In all forms of the invention as above described, it will be evidentthat special provision has been made for retarding the outward travel ofthe drops or sprays of combustion liquids after they engage the targetsurface.

In Fig. a combustion chamber isshown having a cylindrical body portionI0 enclosed by a casing H providing a jacket space 12. The

closed inner end portion of the chamber has a pressure to the jacketspace 12 by a similar feed pipe not shown. The liquids are fed alongconverging lines through feed openings and BI and intermingle in andadjacent the target recess 16. The adjacent parts of the body and endportions of the chamber meet along a sinuous section, as shown in Fig.15, so that the openings 80 and 8| may all be in the same plane and atthe same distance from the point of convergence.

Having thus described certain preferred forms of the invention, theinvention is not to be limited to the details herein disclosed,otherwise than as set forth in the claims, but what is claimed is:

1. A mixing target for a combustion chamber comprising aconically-recessed closed end wall having a plurality of concentricridges projecting substantially normal from the inner and concave faceof said wall, and said ridges being effective to retard radial outwarddisplacement of combustion liquids directed against said closed wall ofsaid mixing target and adjacent the axis thereof, and said ridgesincreasing in height from the axis outward.

2. A mixing target for a combustion chamber comprising aconically-recessed closed end wall having a plurality of concentricridges projecting substantially normal from the inner and concave faceof said wall, and said ridges being effective to retard radial outwarddisplacement of combustion liquids directed against said closed wall ofsaid mixing target and adjacent the axis thereof, and said ridges beinginterrupted to provide staggered spaced retarding projections.

3. A mixing target for a combustion chamber comprising aconically-recessed closed end wall having a plurality of concentricridges projecting substantially normal from the inner and concave faceof said wall, and said ridges being effective to retard radial outwarddisplacement of combustion liquids directed against said closed wall ofsaid mixing target and adjacent the axis thereof, and said ridgesincreasing in height from the axis of said wall outward and being ofcurved and hooked cross-section.

4. A mixing target for a combustion chamber comprising acomically-recessed closed end wall having a plurality of concentricridges projecting substantially normal from the inner and concave faceof said Wall, and said ridges being effective to retard radial outwarddisplacement of combustion liquids directed against said closed wall ofsaid mixing target and adjacent the axis thereof, and said ridgesincreasing in height from the axis of said wall outward and being ofcurved and hooked cross section and with the hooked edges thereofdirected outward and away from the axis of said target.

5. A mixing target for a combustion chamber comprising aconically-recessed closed end wall having a plurality of concentricridges projecting substantially normal from the inner and concave faceof said wall, and said ridges being effective to retard radial outwarddisplacement of combustion liquids directed against said closed wall ofsaid mixing target and adjacent the axis thereof, and said ridgesincreasing in height from the axis of said wall outward and being ofcurved and hooked cross section and with the hooked edges thereofdirected inward and toward the axis of said target.

ESTHER C. GODDARD,

Execatrz'sc of the Last Will and Testament of Robert H. Goddard,Deceased.

(References on following p ge) 5 6 REFERENCES CITED FOREIGN PATENTS Thefollowing references are of reeerd in the Number Country Date file ofthis patent: 284,289 Great Britain Oct. 11, 1928 i 522,313 Great BritainJune 14, 1940 UNITED STATES PATENT? 5 633,667 Germany Aug. 3, 1936Number Name Date 729,926 France May 3, 1932 5 29 fvg- 950.399 FranceSept. 11, 1939 a ms une 316,581 Stratton 14111 38, 1885 OTHER REFERENCES1,502,045 McCarry Ju1y-'22, 1924 10 Astronautics, Journal of TheAmerican 1,509,448 Skinner Sept. 23, 1924 Rocket Society, Number 33 ofMarch 1936, pages 2,058,823 Pigott 001;..27, 1936 8 and 12. 9 2,085,800Goddard 1 J1 11yi"6, 1937 Rocket Problems, page 71, book by Lasser2,100,143 Mock Now- 23, 1937 (1931). 2,259,011 Taylor 00137 14, 1941 15Aviation," January 1944, page 148.

2,511,992 Quick June 20, 1950

